Power hacksaw grinding machine



Aug. 31, 1937. WDE L N ETAL 2,091,501

POWER HACKSAW GRINDING MACHINE Filed Sept. 24,. 1935 5 Sheets-Sheet l N 0/0 12? aflminveiz I g m I Q r I MW.

Aug. 31, 1937. w. DE LONG ET AL POWER- HACKSAW GRINDING MACHINE Filed Sept. 24, 1955 5 Sheets---Sheet 2 Aug. 31, 1937. w 5 LONG ET AL 2,091,501

' POWER HACKSAW GRINDING MACHINE Filed Sept. 24, 1935 7 5 Shets-Sheet s Aug. 31, 1937. w. DE LONG ET AL POWER HACKSAW GRINDING MACHINE Filed Sept. 24, 1935 5 Sheets-Sheet 4 Orxmww.

Aug. 31, 1937. w. DE LONG ET AL POWER HACKSAW GRINDING MACHINE Filed Sept. 24, 1955 5 Sheets-Sheet 5 GUM M54 3mm Walieflflezai g Patented Aug. 31, I937 @YUNiTE o STATES-x;

POWER. HAGKSAWGRINDING MA HINE Walter De Long and" Chris Cf'Andersen; South gate; Calif., assignors-to Velvet-Power Hacksaw Grinding Machine 00., Southgate, C'alifiz.

Application September 24, 1935,.SerialNor 41,947.

3 Claims.

lhis invention relates to a machine designed for grinding and resharpening power hacksaw blades, the primary object of the invention being to provide a machine of thischaracter which ;'.Wi1l automatically move the saw to bring the teeth of the saw successively into position to be ground and sharpened. Another object of the invention is to provide means for automatically moving the saw towards and away from the grindsing wheel, as the saw blade under'operation is being advanced to bring another tooth into a position to be ground.

A further object of the invention is to provide means for adjusting the throw of the machine-to the end that an adjustment may be made adapting the'machinefor use in grinding saws'wherein theteeth are of various sizes.

With the foregoing and other objects in View; which will appear as the description proceeds,

the invention resides in the combination and-are rangement of parts and in the detailsaofi con:

structionhereinafter described and claimed; it"

being understood that changes in the precise embodiment of' the invention herein disclosed,- may ,be-pmadewithin the scope of what is claimed,-

without departing from the spirit of the in-- vention.

In thedrawings:

Figure 1 is a plan view of a machine constructed .in accordance with the invention.

Figure 2 is a front elevationallview thereof.

Figure 3is aside elevationalview of the machine Figure 4 is a sectional view taken-on line. 4-4

'. of Figure 1. I

Figure 5 is a sectional view taken on line 5--5 of Figure 3.

Figure 6' is a sectional View taken on line 6--6-f,

of Figure 5.

Figure '7 is a fragmental plan View illustrating the levers for advancing the saw to the grinding wheel.

Figure 8is a sectional view taken on line 8'8-;of-

chine on which the motor. grinding wheeland other mechanism. of the machine, are supported,

The grinding wheel is indicated by the reference character 6; andlis; mounted on the shaft 1 that is heldin' bearingsi mounted within the tubular support 8; Thetubularsupport 8 embodies a base 9 with-elongated openings-. -.lll for the reception of the bolts I I' that secure-the base inlposition on the base'5'. Due to the construction of the openingsalll, it will be seen that-the grinding wheel 6 may; be adjusted: longitudinally of the base 5, compensating for wear and stretch of the V- belt l5. g

A pulley indicatedat I2'is mounted on one end-of the shaft! and receives motion from the pulley Iii-mounted on the power shaft I4, through the belt-l 5. The shaft is rotated by the motor I6;'which.isof the electric type.

The shaft l4-is formed with-a worm I! that meshes withthezgeart IB-that in turn is secured. tothe vertical shaft l9rthat extends through the casing 20 in which thevgearlaoperates.

Mounted on the upper end: of the shaft [9, is a head 'ZOiQsecured to the shaft by means of the pinaZl: that'extendszthrough the head and shaft. Risingxfrom thewhead 20" and disposed eccentrically thereof, is ashaft 22 on which the yoke 23 is m'ounted,;the yoke being secured in position by means of the nut 24.

Pivotallyiconnected with the yoke 23, is a shaft ZSkthatzextends into the sleeve 26, the sleeve and shaft being-threaded, so that an adjustment of the shaft may be made. On one end of the sleeve 26. is alhand' wheel 21y bymeans of which the sleeve 26 may besmoved with respect to the shaft 25.-

Ononeiend ofthesleeve is an enlargement 28, the. outer surfaceof which is curved to fit within the socket 29 carried by thechuck support 30, so that pivotal movement of the shaft 25-andisleeve 26 with=respectto the chuck, will bepermitted; The chuck support includes an arm 3-l which ishpivotallymounted on thebase, at"32'.' 'A'slot', for-thereception of the saw blade to-"be sharpened; is formed longitudinally of the chucksupporhand is-of a depth to receive the saw-ibladeyin: sueh"a way that. the teeth of the blade-iwill extend beyond theforward. edgeof the chuck where they may contact with the grinding Wheel 36; Springpressed balls 34' extend through the chuck and: frictionally engage the upper surface 0f: the saw .blade under treatment, withthe result that the saw may be moved'longitudinally of the chuck, inla manner to .be hereinafter more fully dscribed but will be securely held against movement, while the grinding Wheel 6 is. contacting therewith, during the grinding operation Adjusting bolts Q35 operate through the chuck and engage the rear'edge of the saw blade held in the chu'c'kg'lthe saw blade being shown in dotted lines in Figure 1 of the drawings and indicated by the reference letter A. These adjusting screws operate to move the saw blade to its proper position where it may be ground by 5 the wheel 6.

The head 20' is in the form of a cam, as clearly shown by Figure 1 of the drawings and as this head rotates, it engages the wheel 36 carried on the inner end of the shaft 31', there being provided a spring 38 for cushioning the movements of the shaft 31.

This shaft 31 is mounted on the arm 38' that is secured to the shaft 39 mounted in bearings 40 in such a way that the shaft 39 may rotate aprel5 determined distance. At the opposite end of the shaft 39, is a vertical arm 4| pivotally mounted on the shaft 32, so that the arm 4| may rock with the chuck, when the chuck is moved by the action of the shaft 25. The upper end of the arm 4| is forked and straddles the shaft 42, the connection between the arm 4| and shaft 42 being madethrough the adjustable nuts 43, which are shown as mounted on the shaft 42. Forming a part of the chuck, are vertical shafts 44 to which the arms 45 are connected, the'arms 45 having forked ends that straddle the shaft 42, whereby movement of the shaft 42 will cause the arms 45 to rock.

At the upper ends of the shafts 44, there are arms 46 that are secured to the shafts to swing therewith. These arms'46 extend forwardly to positions adjacent to the teeth of the saw held within the chuck.- On the outer ends of the arms 46, are pawls 41 that swing forwardly to engage the teeth of the saw blade, as shown by Figure '7 of the drawings,-under the action of the coiled springs 48. Adjusting screws 49 are used in connection with the pawls 41 and provide means for adjusting the pivotal movements of the pawls 41. Thus it will be seen that as the arms swing forwardly, the pawls 41 will engage the teeth of the saw blade, moving the saw blade so that the tooth next to the tooth ground, will be brought into position opposite to the grinding wheel so that when the-chuck is moved towards the grinding wheel and to the limit of its forward movement, the tooth will be ground and resharpened.

In order that various sized saw teeth may be 50 sharpened, adjusting screws 53 and 54 are provided near the arms 46, one of the arms 46 operating between the adjacent ends of the screws 53 and 54. By moving these adjusting screws 53 and 54 the stroke of the arm 45 operating there- 55 between, may be adjusted.

Pivotally supported on the frame of the machine are arms 55 that carry rollers 56"which move over the teeth ofthe saw under treatment, as the saw is moved through the chuck, advanc- 60 ing the teeth to positions to be ground. These arms and rollers provide stops restricting movement of the saw blade forwardly on the chuck and with respect to the chuck. Coiled springs 51 are connected with the arms 55 and normally 5 urge the arms and rollers supported thereby towards the saw blade. In the form of the invention as shown by Figures 9 and 10 of the drawings, the arms 50 are provided with bars 5| pivotally mounted at theouter ends of the arms 50,

70 the bars 5| having teeth adapted to mesh with the teeth of the saw blade being sharpened.

This type of feeding mechanism is used when a saw blade is being sharpened wherein certain of the teethhave been broken out. I 75 From the foregoing it will be seen that due to Having thus described the invention, what is claimed is:

1. A hacksaw blade sharpening machine comprising a base, a grinding wheel on the base, a motor mounted on one end of the base, means for transmitting movement of the motor to the grinding wheel, a power shaft mounted on the base and operated by the motor,- a chuck pivotally mounted at the opposite end of the base, means for securing a saw blade to the chuck, a vertical shaft mounted on the base, and operated by .the power shaft, a head eccentrically mounted on the vertical shaft providing a cam, a stub shaft rising from the head and mounted eccentrically with respect to the head, a yoke mounted on the stub shaft, a shaft connected to the yoke and reciprocated as the yoke is rotated, the opposite end of the shaft being connected to the chuck, moving the chuck toward and away from the grinding wheel, and means operated by the cam for moving the saw blade transversely of the chuck, advancing the blade whereby the teeth of the blade are successively brought into engagement with the grinding wheel.

2. A hacksaw blade grinding machine comprising a base, a grinding wheel, a motor mounted on the base, means for transmitting movement of the motor to the grinding wheel, a vertical shaft operated by the motor, a head eccentrically mounted on the shaft providing a cam, a stub shaft rising from the head and mounted eccentrically with respect to the head, a saw blade chuck mounted adjacent to the grinding wheel, a yoke mounted for rocking movement on the stub shaft, a shaft connecting the yoke and chuck whereby rotary movement of the stub shaft rocks the chuck, moving the saw blade into and out of contact with the grinding wheel, and means operated by the cam for operating the saw moving the saw transversely of the base.

3. A hacksaw blade sharpening machine comprising a base, a motor mounted on the base, a grinding wheel mounted on the base and operated by the motor, a saw blade chuck pivotally mounted on the base, arms pivotally mounted on the chuck, pawls pivotally mounted on the outerends of the arms and engaging the'teeth of the saw whereby pivotal movement of the arms feeds the saw blade transversely of the chuck, successively advancing the teeth of the saw blade to positions opposite to the grinding wheel, a horizontal shaft on the base, a cam operated by the motor, an arm connected with the shaft, a shaft mounted on the arm, a -roller carried at one end of the latter shaft and engaging the cam whereby the latter shaft and horizontal shaft are rocked laterally, means for transmitting movement of the horizontal shaft to the first mentioned arms and saw blade mounted on the chuck, and means for moving the chuck towards and away from the grinding wheel.

WALTER DE LONG. CHRIS C. ANDERSEN. 

